Prospects for comprehensive immigration reform in the new Democratic Congress are on the rise. Voters in November failed to rally around the tough anti-immigration rhetoric of the Republican House majority, replacing the GOP Congress with Democratic leadership that has shown itself more open to expanding legal channels for immigrant workers.

Nonetheless, momentum is building for major reform – and not a minute too soon. In testimony before the Senate Judiciary Committee earlier this month, Commerce Secretary Carlos Gutierrez remarked that America’s dynamic economy continues to create jobs for low-skilled workers as well as higher skilled ones, yet the number of native-born Americans willing to fill lower-end jobs continues to shrink.

From 1996 to 2004, the number of adult Americans without a high school education – the demographic group that typically fills low-skilled jobs – fell by another 4.6 million. The biggest flaw in our current immigration system is its lack of a sufficient legal channel for low-skilled immigrants who are crucial to filling that gap between demand and supply on the lower rungs of the labor ladder. In the face of those powerful economic and demographic trends, federal enforcement efforts have failed to stem the inflow of low-skilled immigrants.

Because of the cost and risk of crossing the border, the still-large number of illegal immigrants who make it across are more likely to stay for an extended period once inside the country. Enforcement efforts intended to reduce illegal immigration have perversely increased the illegal population by reducing what had historically been a circular flow of migration from and back to Mexico.

Homeland Security Secretary Michael Chertoff, after reporting the administration’s increased efforts at border enforcement, told the committee that a policy of enforcement only cannot work. He called on Congress to create a temporary worker program so that foreign workers can enter the United States legally to fill jobs that U.S. workers do not want.

“This regulated channel for temporary workers would dramatically reduce the pressure on our borders, aid our economy and ease the task of our law enforcement agents inside the country,” Chertoff told the committee. “There is an inextricable link between the creation of a temporary worker program and better enforcement at the border.”

The last major effort by Congress to stop illegal immigration was the Immigration Reform and Control Act of 1986. IRCA failed because it lacked any expansion of legal immigration to meet the labor needs of the U.S. economy. It did legalize 2.7 million previously illegal immigrants and ramped up enforcement, but because it made no allowance for the entry of new, legal workers, the population of illegal immigrants soon began its inevitable increase to the current level of an estimated 12 million.

For immigration reform to succeed, it must contain a workable temporary worker program. Such a program must create a sufficient number of visas to meet the needs of the U.S. economy. A crucial flaw in the McCain-Kennedy immigration reform passed by the Senate in May of 2006 was that it capped annual visas at 200,000, a number far below the actual demand of the U.S. labor market.

According to Labor Department projections, our economy will continue to create a net 400,000 or more low-skilled jobs annually in service sectors like food preparation, cleaning, construction, landscaping and retail. Any visa cap below the actual demand in our economy will only perpetuate the problem of illegal immigration.

True reforms must also avoid stifling labor regulations that discourage legal hiring. Union leaders are pressuring Democrats to require that temporary workers be paid “prevailing wages” – that is, artificially high, union-level wages rather than market wages. This would be a recipe for failure, since many of the jobs filled by immigrant workers are low-skilled, low-wage jobs that would simply not exist in the legal economy if union-level wages were mandated. Adding cumbersome labor rules will only perpetuate the underground labor market that has been created by the current system.

Finally, any reform worthy of the name must offer a path to legalization for the millions of undocumented workers already in our economy and society. Deporting them all would be impractical – to say nothing of an economic and humanitarian disaster – yet continuing indefinitely with millions living in a legal twilight zone is also unacceptable.

Opponents of immigration will label any legalization plan as “amnesty,” but the smear is inaccurate for most ideas on the table. Those gaining legal status would be required to pay a fine and back taxes, and they could also be required to return briefly to their home countries to apply for legal entry.

Waiting won’t make the problem go away. If the new Congress fails to enact comprehensive immigration reform, the alternative will be two more years of widespread illegal immigration, and no one but the smugglers at the border will benefit by it.